I wanna install one app. There is something wrong. When I click "Install", the download won't start.

It seems stay pending. I can see the dot above is running. I'm waiting for 1 hour. It stays at "Pending" and can't clicked. What should I do?

The store apps are a work in progress. I have read somewhere that they may or may not be working at present. You might try again at another time or wait until a RC is released. The Metro apps have been the most unfinished portion of Win 8 CP.